| abstract |
The invention relates to a method for continuously producing a mixture of phthalic acid and phthalic anhydride dissolved in an aliphatic monocarboxylic acid, preferably in acetic acid, by means of oxidation of o-xylene dissolved in the monocarboxylic acid by means of atmospheric oxygen, the oxidation being performed in the presence of a catalyst, characterized by several reaction stages, the molar ratio of o-Xylene to the intermediate products composed of 2-methylbenzaldehyde, 2-methylbenzoic acid, and phthalide being less than 1:40 in the product flow (7) fed to the last reaction stage. |